Unit for repairing and inflating inflatable articles

ABSTRACT

A unit for repairing and inflating an inflatable article defines a volume for a sealing fluid; a compressed-air inlet connectable to a pressure source; an outlet connected fluidically to the inlet by the volume to inject sealing fluid into the inflatable article by means of compressed air; and a pressure regulating unit having an outlet node upstream from the volume, a first air resistance for reducing air pressure to the volume, a bypass line connected to the outlet node and parallel to the first air resistance, and a selector connected to the first air resistance and the bypass line.

TECHNICAL FIELD

The present invention relates to a unit for repairing and inflatinginflatable articles, such as a punctured vehicle tyre.

BACKGROUND ART

A punctured tyre can be replaced with a spare wheel stowed in acompartment on the vehicle, e.g. under the floor of the boot, in thecase of a car.

The spare wheel, however, is bulky, and takes up space in the boot,which could be put to better use.

The spare wheel is also heavy, which makes changing the wheel difficult,especially in the case of a large spare wheel of a heavy-duty vehicle.

Repair and inflation kits are also used, to enable punctures to berepaired without removing the wheel.

Known kits comprise a sealing fluid canister; and a dedicated compressorconnected to the canister. In the event of a puncture, the canister isconnected by a hose to the tyre, and the dedicated compressor is turnedon.

The compressed air injects the sealing fluid into the tyre, and inflatesthe tyre once the fluid increases in viscosity and seals the puncture.

Known kits normally feature a reciprocating dedicated compressor poweredby an electric motor. Compressors of this sort are relatively noisy andbulky, especially those designed to inflate large, heavy-duty vehicletyres.

Some, e.g. heavy-duty, vehicles are equipped with their own on-board aircircuit, the air pressure of which, however, may not be suitable forinjecting the sealing fluid, and may cause malfunctioning. Morespecifically, an on-board, heavy-duty vehicle air circuit comprisesaccumulators to maintain constant pressure and cater to sudden demand byactuating devices. When a repair unit, however, is connected to the aircircuit, the high pressure causes hammering and surging, Which damagethe unit; the small orifices of the valve closing the sealing fluidcanister may cause clogging; and high pressure also causes prematurepolymerization of the sealing fluid, which may result in partial orcomplete clogging of the feed lines.

On the other hand, the high pressure of on-vehicle air circuits enablesfaster inflation of the tyre and, therefore, shorter hold-ups to carryout the repair.

DISCLOSURE OF INVENTION

It is an object of the present invention to provide a unit for repairingand inflating inflatable articles, designed to eliminate the abovedrawbacks.

According to the present invention, there is provided a unit forrepairing and inflating inflatable articles, the unit defining a volumefor containing a sealing fluid; an inlet and outlet connectedfluidically to each other by the volume; and releasable fluidicconnecting means for connecting the inlet to an outlet port of a vehicleair circuit comprising a pressure source and at least one actuator.

The repair and inflation unit also comprises a valve assembly located inseries with the sealing fluid canister and designed to regulate the airinput pressure to the canister. More specifically, the valve assembly isdesigned to operate selectively in a first operating configuration, inwhich the input pressure is reduced to a suitable injection value; and asecond operating configuration, in which the input pressure to thecanister is higher than in the first operating configuration of thevalve assembly.

In other words, the input pressure to the sealing fluid canister isregulated, i.e. reduced, to achieve correct outflow of the sealing fluidfrom the canister to the tyre; and high pressure can be restored forfaster inflation.

Moreover, the repair and inflation unit has no dedicated compressor,pressure being generated by a compressor already on the vehicle andmainly designed to control part of the vehicle, e.g. the brakes.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred, non-limiting embodiment of the present invention will bedescribed by way of example with reference to the accompanying drawings,in which:

FIG. 1 shows a view in perspective of one embodiment of the presentinvention;

FIG. 2 shows a fluidic diagram of the FIG. 1 repair and inflation unit;

FIG. 3 shows a fluidic diagram of a further embodiment of the presentinvention.

BEST MODE FOR CARRYING OUT THE INVENTION

Number 1 in FIG. 1 indicates as a whole a tyre repair and inflation unitconnectable to a vehicle air circuit comprising a compressed-airgenerator connected rigidly to a fixed structure of the vehicle. e.g.the frame; an actuator, e.g. a vehicle brake actuator; and an outletport to which to connect unit 1.

Unit 1 comprises a sealing fluid canister 8 connected to an inlet 9 forcompressed air from the air circuit of a pressure source, such as thevehicle air circuit.

More specifically, canister 8 comprises a bottle 11; a dispenser unit(not shown) connecting inlet 9 to bottle 11; and a hose 12 connectingbottle 11 to a tyre. Bottle 11, the dispenser unit, and hose 12preferably define a single, replaceable unit, i.e. which is replacedwhen the bottle is empty or the sealing fluid is past its use-by date.

Canister 8 preferably comprises an internal valve (not shown) connectinginlet 9 fluidically to hose 12 via an inner volume 13 of bottle 11, andmay be made as described in International Patent ApplicationWO-A1-2005084968 filed by the Applicant.

Unit 1 also comprises a pedestal 14 connected to canister 8 byreleasable connecting means, e.g. a threaded connection or fast-fitcoupling, and defining inlet 9.

More specifically, the releasable connecting means are such that, whenrepairing and inflating the tyre, canister 8 is set to a substantially,though not necessarily, vertical operating position, in which hose 12,connected to the dispenser unit of canister 8, faces downwards and isinterposed between bottle 11 and a supporting surface S on whichpedestal 14 rests (FIG. 1).

Pedestal 14 comprises a supporting body 15, to which canister 8 isfitted; and a secondary body 16 connected rigidly to supporting body 15and defining with it an annular recess 17.

Pedestal 14 is substantially symmetrical with respect to a plane n (onlyshown partly in FIG. 1), and secondary body 16 is smaller than thesupporting body in a direction perpendicular to plane n.

Pedestal 14—preferably supporting body 15—defines two seats 18 adjacentto supporting surface S, and, in this non-limiting embodiment, but notexclusively for the purpose of the present invention, comprises twoextractable arms 19 which withdraw inside seats 18. Arms 19 arepreferably symmetrical with respect to plane n, and define respectivesupports for pedestal 14 in a direction perpendicular to plane n.

Supporting body 15 is cylindrical, and defines annular recess 17 tohouse hose 12 connected to the dispenser unit of canister 8.Accordingly, arms 19 are arc-shaped and hinged to respective peripheralportions 20 of supporting body 15, so they are concentric withsupporting body 15 when withdrawn.

Unit 1 also comprises a pressure regulating unit 29 mounted upstreamfrom volume 13 to adjust the air pressure to bottle 11 to the bestsealing fluid injection pressure. More specifically, the pressureregulating unit (FIG. 2) comprises a selector valve 30; and a first andsecond regulating valve 31, 32 connected, parallel to each other, toselector valve 30, and the respective outlets of which join up at a node33 series connected to canister 8.

Pressure regulating unit 29 is located in series between inlet 9 andcanister 8, and adjusts pressure discretely to achieve the best sealingfluid injection pressure, and the best tyre inflation pressure, asdescribed in detail below.

More specifically, regulating valve 31 is an air resistance thatproduces a pressure drop to reduce the pressure of node 33 and canister8 to a suitable pressure to inject the sealing fluid from bottle 11.

Regulating valve 32 is a second air resistance which, between its inletand outlet, produces a smaller pressure drop than regulating valve 31,so that, when selector valve 30 directs compressed airflow to regulatingvalve 32 and closes off access to regulating valve 31 (the oppositeconfiguration to the one shown in FIG. 2), the airflow pressure atcanister 8 is higher than when selector valve 30 directs airflow toregulating valve 31 and closes regulating valve 32 (FIG. 2configuration).

In a preferred embodiment, each regulating valve 31, 32 is a non-returnvalve comprising a shutter, and a spring pressing the shutter into theclosed position. To operate as described above, the spring of regulatingvalve 31 has a greater modulus than the spring of regulating valve 32.

In another preferred embodiment of the present invention, the modulus ofthe springs of regulating valves 31, 32 can be user-adjusted, preferablymanually.

Unit 1 also comprises a display device for showing the user wheninjection is completed, i.e. when the sealing fluid in bottle 11 runsout, and inflation can begin. In a preferred embodiment of the presentinvention, the display device is passive, and comprises a tube, the wallof which has at least one portion made of transparent or semitransparentmaterial, so the user can see whether or not there is sealing fluidflowing along the tube. The tube defines hose 12, and, during use, thedisplay device enables the user to check continued flow of sealing fluidalong hose 12. When the display device shows no flow of sealing fluidalong hose 12, the user may switch selector valve 30 to directcompressed airflow to regulating valve 32. Selector valve 30 preferablycomprises a knob 35, and has a rotary shutter connected to knob 35,which the user turns to switch the selector valve.

To check tyre pressure during inflation, unit 1 comprises a gauge 36located between inlet 9 and a ring nut 37 connected to hose 12 and whichscrews onto the safety valve of the tyre. Gauge 36 preferably picks upthe pressure signal along a line 38 connecting node 33 to canister 8.

Unit 1 comprises a second hose 40 parallel to canister 8 with respect toinlet 9. Hose 40 receives compressed air directly from inlet 9, andserves solely to inflate the tyre when checking tyre pressure.Accordingly, hose 40 is also connected to a gauge; and gauge 36 ispreferably connected to both line 38 and hose 40 by an OR fluidicselector 41.

Unit 1 also comprises a second selector valve 42 for selecting a repairpath, in which inlet 9 is connected to canister 8, or an inflation-onlypath, in which inlet 9 is connected to hose 40.

Unit 1 also comprises a pressure reducer between inlet 9 and hose 40, sopressure can also be reduced when checking tyre pressure, as opposed torepairing the tyre.

For example, the pressure reducer is a continuously-adjusted valvedefining a variable air resistance along hose 40 by constriction.Starting with the valve in the closed position, the user can increasetyre pressure by gradually relieving the constriction. A spring may alsobe provided to restore the pressure reducer to the closed position whenpressure is no longer being regulated by the user.

In a preferred embodiment, the pressure reducer is incorporated inselector valve 42, which is a continuously-adjusted valve, at least asregards opening and closing hose 40.

Clearly, changes may be made to the unit for repairing and inflatinginflatable articles as described and illustrated herein without,however, departing from the scope of the present invention as defined inthe accompanying Claims.

For example, regulating valve 32 may be eliminated, and regulating valve31 is located parallel to a bypass line 43 which produces no significantpressure drop between selector valve 30 and node 33.

Two dedicated gauges may also be provided, one connected betweenselector valve 42 and ring nut 37, preferably between node 33 andcanister 8, and the other connected to hose 40, downstream from selectorvalve 42.

Arms 19 may be connected differently to move between a withdrawn andextracted position, e.g. may be straight and slide along runners definedby pedestal 14.

Hose 40 and selector valve 42 may be eliminated, in which case, inlet 9is connected to canister 8 solely by pressure regulating unit 29.

Node 33 may also be located downstream from inner volume 13. In whichcase, bypass line 43 is connected to hose 12 downstream from canister 8.In this case, too, compressed airflow can be directed by selector valve30 both through regulating valve 31 and through regulating valve 32 orbypass line 43. As in the previous example, regulating valve 32 producesa lower pressure drop than regulating valve 31, or is eliminated, so thepressure along bypass line 43 is higher than the input pressure tocanister 8, and compressed air flows faster along bypass line 43. On theother hand, a relatively low pressure to canister 8 improves outflow ofthe sealing fluid, and reduces the likelihood of the fluid coagulating.

1. A unit for repairing and inflating an inflatable article, the unitdefining a volume (13) for a sealing fluid; a compressed-air inlet (9)connectable to a pressure source; an outlet (37) connected fluidicallyto said inlet (9) by said volume (13) to inject sealing fluid into saidinflatable article by means of compressed air; and a pressure regulatingunit (29) having a first air resistance (31) for reducing air pressureto said volume (13), a bypass line (43) parallel to said first airresistance (31), and a selector (30) connected to said first airresistance (31) and said bypass line (43); said first air resistance(31) producing a higher pressure drop than that along said bypass line(43) when compressed air flows.
 2. A unit as claimed in claim 1,characterized by comprising a second air resistance (32) along saidbypass line (43).
 3. A unit as claimed in claim 2, characterized in thatsaid second air resistance (32) produces a smaller pressure drop thansaid first air resistance (31).
 4. A unit as claimed in claim 1,characterized in that said first air resistance (31) is a valve.
 5. Aunit as claimed in claim 4, characterized in that said valve is anon-return valve.
 6. A unit as claimed in claim 1, characterized bycomprising a device (12) for showing the user when the sealing fluid insaid volume (13) runs out.
 7. A unit as claimed in claim 6,characterized in that said device (12) is a passive display device.
 8. Aunit as claimed in claim 7, characterized in that said device (12)comprises a tube connected fluidically downstream from said volume (13),and comprising at least one portion made of material through whichsealing fluid flow is visible.
 9. A unit as claimed in claim 1,characterized by comprising a second selector (42); and a hose (40)parallel to said volume (13) and said pressure regulating unit (29),with respect to said second selector (42).
 10. A unit as claimed inclaim 9, characterized by comprising a third air resistance (42) forregulating pressure along said hose (40).
 11. A unit as claimed in claim1, characterized in that said bypass line is connected downstream fromsaid outlet (37).